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Collembola can be used as the model organism in the ecotoxicological tests in the soil environment. Currently, two standard bioassays are available (reproduction test in soil and avoidance behaviour test), which are highly sensitive to soil contamination. However, both of those tests have some limitations. Therefore, based on our preliminary research, we propose the alternative test of growth inhibition of springtails as a screening tool to assess the risk related to soil contamination. In this study, the growth inhibition of Collembola species Folsomia candida was analyzed as a response to soil contamination with arsenic: As(III) and As(V). Thus, twenty, 12-day-old juveniles of Collembola, were exposed to 8 concentrations of As in soils, in 6 replicates. The experiment was conducted at two soil pHs (natural and reduced). The endpoint of the test was the reduction in collembolan body size compared to the control soil, measured for all the survivors. More precisely, the feature on which this test is based in the length of the springtail body measured from the beginning of the antennae to the end of the abdomen. It was found that Collembola decrease their body sizes under soil contamination with As. Lower toxicity was found for As(V) in comparison to As(III). For As(V) the decrease in soil pH slightly increased the toxicity effect on Collembola. The effect of growth inhibition significantly correlates with the mortality and reproduction inhibition of Collembola. To conclude, this method can be applied in testing the toxicity of As in the soil as an alternative to the standard methods. However, it needs further investigations considering the exposure time and comparison to the standard methods.

The current animal-based paradigm for safety assessment must change. In September 2016, the UK National Centre for Replacement, Refinement and Reduction of Animals in Research (NC3Rs) brought together scientists from regulatory authorities, academia and industry to review progress in bringing new methodology into regulatory use, and to identify ways to expedite progress. Progress has been slow. Science is advancing to make this possible but changes are necessary. The new paradigm should allow new methodology to be adopted once it is developed rather than being based on a fixed set of studies. Regulatory authorities can help by developing Performance-Based Standards. The most pressing need is in repeat dose toxicology, although setting standards will be more complex than in areas such as sensitization. Performance standards should be aimed directly at human safety, not at reproducing the results of animal studies. Regulatory authorities can also aid progress towards the acceptance of non-animal based methodology by promoting "safe-haven" trials where traditional and new methodology data can be submitted in parallel to build up experience in the new methods. Industry can play its part in the acceptance of new methodology, by contributing to the setting of performance standards and by actively contributing to "safe-haven" trials., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)